The updated TWELP 2400 bps vocoder  provides high speech quality like GSM AMR 4.75 kbps vocoder, operating on twice more bit rate  

 
LanguageAMR 4750TWELP 2400MELPe 2400
American 3.351 3.330 3.077
Arabic 3.277 3.253 3.053
British 3.272 3.181 3.019
Chinese 3.267 3.307 2.970
Danish 3.311 3.275 3.022
Dutch 3.089 3.114 2.830
Finnich 3.166 3.049 2.791
French 3.277 3.325 3.106
German 3.321 3.183 2.998
Greek 3.206 3.275 3.004
Hindi 3.286 3.246 3.089
Hungarian 3.305 3.279 3.086
Italian 3.462 3.363 3.226
Japanese 3.369 3.407 3.188
Norwegian 3.267 3.286 3.032
Polish 3.263 3.267 3.029
Portuguese 3.377 3.350 3.146
Russian 3.186 3.165 2.952
Spanish 3.343 3.294 3.048
Swedish 3.391 3.269 3.147
Average3.2893.2613.041

Superiority of the TWELP 2400 bps vocoder over MELPe 2400 bps is on average 0.220 PESQ and just -0.028 PESQ in comparison with AMR 4750 bps

 

Highest speech quality in very noisy channel

 TWELP 4800 bps Robust vocoder

 TWELP 3600 bps Robust vocoder

 TWELP 2400 bps Robust vocoder

 
BER %MELPe 2400TWELP 2400 Robust (HD)TWELP 2400 Robust (SD)
0 3.041 3.109 3.109
1 2.513 3.019 3.049
2 2.186 2.943 2.986
3 1.940 2.790 2.934
4 1.748 2.562 2.888
5 1.582 2.301 2.822

You can play and listen short samples of the source speech as well as the speech processed by both vocoders in AWGN channel with BER = 5% for any of 20 languages, using links in the table below.

LanguageSource speechMELPe 2400 (BER = 5%)TWELP 2400 Robust (BER = 5%)
American
Arabic
British
Chinese
Danish
Dutch
Finnich
French
German
Greek
Hindi
Hungarian
Italian
Japanese
Norwegian
Polish
Portuguese
Russian
Spanish
Swedish

 

Our TWELP vocoders are used in the best transceivers from world leaders

icom f8101

barret 4050

rapidm RA7 4050

 

TRC1193B

 

TRC1193V

More...

 

 

 Newest TWELP 700 bps vocoder is free of export restrictions and provides very high speech quality 

 
LanguageTWELP 700 bpsTWELP 600 bpsMELPe 600 bps
American 2.724 2.617 2.397
Arabic 2.603 2.47 2.254
British 2.678 2.559 2.414
Chinese 2.643 2.471 2.189
Danish 2.638 2.471 2.227
Dutch 2.475 2.374 2.173
Finnich 2.472 2.367 2.249
French 2.693 2.539 2.34
German 2.667 2.521 2.287
Greek 2.595 2.457 2.212
Hindi 2.660 2.549 2.403
Hungarian 2.659 2.520 2.359
Italian 2.837 2.705 2.428
Japanese 2.792 2.576 2.436
Norwegian 2.640 2.433 2.225
Polish 2.664 2.511 2.294
Portuguese 2.712 2.558 2.393
Russian 2.591 2.414 2.156
Spanish 2.648 2.525 2.389
Swedish 2.725 2.562 2.430
Average2.65582.509952.31275

Superiority of the TWELP 700 is on average 0.14(!) and 0.34 (!!!) PESQ appropriately